- Copyright © 2002 Society of Exploration Geophysicists
Oil and gas reservoirs need to be optimally managed for economic, physical, political, and environmental reasons. Creating a reservoir model assists management by analysis of reservoir behavior and forecasting production forecast. Thus, the quality of the reservoir model—i.e., the degree to which it represents the actual reservoir—directly affects reservoir management.
During the lifetime of a field, a wealth of data becomes available and is used to constrain the reservoir model. In the exploration phase, the reservoir model is constructed using 3D seismic data, geologic knowledge of the surrounding area, and log/core measurements from a few exploration wells. This input is referred to as “static data.” During the appraisal phase, drilling additional wells provides “dynamic data” in the form of well test data. When the field is in production, the wells provide production data and monitor (time-lapse) seismic surveys might be acquired. The production and time-lapse seismic data, also classified as dynamic data, condition the reservoir model in the inversion process referred to as history matching. This process involves adjusting model parameters (e.g., permeability and other flow properties) until the behavior of the reservoir model “fits” the historical (dynamic) data as observed at the wells and by time-lapse seismic measurements.
The geologic structure of the reservoir model is determined early in the life of an oil field. It is sometimes manually adjusted, but more often kept fixed. However, in structurally complex fields, the geometry of a reservoir is one of the biggest uncertainties and incorrectly identifying structural features, such as fault planes, can have very serious consequences—badly placed wells, by-passed hydrocarbon, poor estimates of oil-in-place, and failure to find hydrocarbons trapped in compartments surrounded by no-flow boundaries or with anomalous flow paths due to the presence of faults.
In this paper, we suggest an automated method to history match the reservoir …